| 摘要 |
<p>A new valve has a casing in two longitudinal sections (2, 4). The plug element (8), is turned by a shaft (10) having an external seal (32), fitting directly into an annular cavity between shaft (10) and casing (2). A second seal (42) is located behind a ring (38) fixed to the casing, where a stuffing bush (48) presses against the second seal. The casing has a cladding (20), preferably plastic. This reaches at least up to, and lies against, the first of the seals. Preferably both seals (32, 34) are mutually conforming, and/or are packings, especially made of polytetrafluoroethylene (PTFE).</p> |
